Shuttle mechanism for sewing machines



April 17, 1962 W. D. SZUBA ETAL SHUTTLE MECHANISM FOR SEWING MACHINES Filed Sept. 23. 1960 2 Sheets-Sheet 1 WITNESS INVENTORS, WALTER 0. 3208A and Jacoa M. BENZ/N6.

TORNEY w. D. SZUBA ETAL 3,029,762

SHUTTLE MECHANISM FOR SEWING MACHINES April 17, 1962 Filed Sept. 25, 1960 2 Sheets-Sheet 2 i ii i r l/// |2 INVENTORS.

WALTER 0. 3208A and WITNESS glTTORNEY JACOB M. BENZ/N6.

United States memo 3,029,762 SHUTTLE MECHANISM FOR SEWING MACHINES Walter D. Szuba, Summit, and Jacob M. Benzing, Elizabeth, N.J., assignors to The Singer Manufacturing Company, Elizabeth, N.J., a corporation of New Jersey Filed Sept. 23, 1960, Ser. No. 58,053

2 Claims. (Cl. 112-192) The present invention relates to sewing machines and particularly to a shuttle mechanism for sewing machines.

The object of this invention is to provide an oscillating type shuttle mechanism primarily adapted for use in a zig-zag sewing machine, which mechanism is designed to facilitate manufacture, assembly and adjustment, and which at the same time is simple, economical, dependable, durable and efficient.

Having in mind the above and other objects that will be evident from an understanding of this disclosure, the invention comprises the devices, combinations and arrangements of parts as illustrated in the presently preferred embodiment of the invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings in which:

FIG. 1 is a bottom plan view of the bed of a sewing machine embodying the present invention.

FIG. 2 .is a vertical sectional view taken substantially on the line 2-2 of FIG. 1.

FIG. 3 is a vertical sectional view taken substantially on the line 3-3 of FIG. 1.

FIG. 4 is a vertical sectional view taken substantially with line 4-4 of FIG. 1.

With reference to the drawings, there is illustrated a sewing machine having a frame including a bed 1 and a standard 2 rising from one end of the bed 1. The bed 1 includes a bed plate 3 which is provided with a cutout that is normally closed by a throat plate 4 and a slide plate 5. The upper surfaces of the bed plate 3, throat plate 4 and slide plate 5 constitute the work supporting surface of the machine. A needle 6 is adapted to penetrate an aperture in the throat plate 4 and defines the point of stitch formation on the work supporting surface of the machine.

Work is fed transversely across the work supporting surface of the machine past the point of stitch formation to define a line of feed by a feeding mechanism including a feed bar 7 carrying a feed dog 8 that operates through slots in the throat plate 4. The feed bar 7 is pivotally connected at the one end at the rear of the bed 1 to an upstanding rocker 9 on a feed advance shaft 16 journaled longitudinally in the bed 1. Oscillation is imparted to the feed advance shaft by a pitman 11 connected to a crank arm 12 on the rocker. At the end at the front of the bed 1, the feed bar 7 is formed with a fork 13 that receives a stud 14 carried by a crank arm 15 and feed lift shaft 16 journaled longitudinally of the bed 1. Oscillation is imparted to the feed lift shaft 16 by a feed lift cam 17 on a bed shaft 18, which cam is embraced by a fork 19 on the feed lift shaft. The bed shaft 18 is journaled longitudinally of the bed 1 beneath the standard 2 and is oscillated by a pitman 20 connected thereto by a crank arm '21.

The shuttle mechanism of the machine comprises a shuttle shaft 22 journaled in the bed 1 in bearing bushings 2.3 and 24 mounted respectively in a lug 25 and a pair of lugs 26 depending from the bed. To impart oscillation to the shuttle shaft 22 there is provided a collar 27 secured thereon outwardly of the bushing 23 and having a crank arm 28 pivotally connected to one end of a if we link 29 which at its other end is pivotally connected to a crank arm 30 on the bed shaft 18.

The bushing 24 is elongated to provide a free end upon which is mounted a sleeve portion 31 of a shuttle housing 32 and which is releasably secured thereon by a pair of screws 33. The shuttle housing 32 also includes a body portion 34 having formed in the front portion thereof an open sided discontinuous circular raceway 35 having an axis parallel to the line of feed and normal to the axis of the shuttle shaft 22. The open side of the raceway 36 is adapted to be closed by a shuttle cap 36 mounted on the body portion 34 for pivotal movement about a' vertical axis by means of a pivot pin 37 carried by a slide plate 38 mounted in a slot in the body portion 34 and having a spring 39 seated in an aperture in the slide plate for biasing the slide plate to hold the shuttle cap resiliently against the body portion. At the point diametrically opposed to the slide plate 38, there is provided a latch 40 pivotally mounted on the body portion 34 by a shoulder screw 41 and adapted to be swung over the shuttle cap 36 to hold it in operative position and to be swung clear of the shuttle cap 36 to permit it to be swung open about the, pivot pin 37. A shuttle 42 is mounted for oscillation in the body portion 34 by means of a peripheral bearing rib 43 journaled in the raceway 35.

The shuttle housing 32 also includes a rearwardly extending bearing portion 44 that receives a bushing 45 in which is journaled a shuttle driving shaft 46. The shaft 46 is arranged coaxially of the raceway 35 and at its forward end carries a shuttle driver 47 inoperative engagement with the shuttle 42 for imparting oscillation to the shuttle open oscillation of the shuttle driving shaft 46. Upon the rearward extension of the shuttle driving shaft 146 there is mounted a pinion 48 that cooperates with an arcuate rack 49 secured upon the end of the shuttle shaft 22 so that upon oscillation of the shuttle shaft 22, oscillation will be imparted to the shuttle driving shaft 46. A sheet metal cover 50 encloses the pinion 48 and rack 49 and is secured to the underside of the bed plate 3 by screws 51.

One of the advantages of the present invention is that the shuttle mechanism can be applied as a unit to the machine. In this manner, the mechanism, including the shuttle housing 32, shuttle 42, shuttle cap 36, shuttle driving shaft 46, shuttle driver 47, bushing 24, shuttle shaft 22, rack 49 and pinion 48, can be completely preassembled as a unit, and can be run in apart from the machine. This subassembly of the shuttle mechanism facilitates manufacture and assembly of the machine.

One of the most important advantages of the present invention is that it facilitates adjustment of the shuttle mechanism relatively to the work supporting surface of the machine. The shuttle 42 includes the loop seizing beak 52 that must pass closely adjacent to the needle 6 to seize the loop of thread therefrom and must pass the needle in timed relation thereto and at a fixed distance beneath the work supporting surface of the machine. The spacing of the shuttle relatively to the work supporting surface of the machine is critical and to obtain this it has heretofore been necessary to perform accurate machining operations, e.g., accurately machining a seating surface on the bed 1 and a comparable surface on the shuttle housing. With the construction in accordance with invention, the shuttle can be readily adjusted relatively to the work supporting surface of the machine by adjusting the shuttle housing singularly about the axis of the shuttle shaft 22 by turning the bushing 24 or by turning the shuttle housing 32 relative to the bushing 24.

Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to a preferred embodiment of our invention which is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.

Having thus set forth the nature of the invention, what we claim herein is:

1. In a sewing machine having a frame including a bed having a bed plate, a needle mounted in said frame for endwise reciprocation and adapted to penetrate said bed plate to define a point of stitch formation thereon, and a shuttle mechanism comprising a shuttle housing, a shuttle driving shaft journaled in said shuttle housing, an internal circular raceway formed in said shuttle housing coaxially of the axis of said shuttle driving shaft, a shuttle having a peripheral bearing rib journaled in said raceway, a shuttle driver carried by said shuttle driving shaft and operatively engaging said shuttle for imparting oscillation to said shuttle upon oscillation of said shuttle driving shaft, a shuttle shaft journaled longitudinally in said bed on an axis parallel to said bed plate, means for imparting oscillation to said shuttle shaft, means for mounting said shuttle housing in said bed with said shuttle driving shaft on an axis normal to the axis of said shuttle shaft and substantially parallel to said bed plate and for angular adjustment of said shuttle housing about the axis of said shuttle shaft and with said shuttle disposed in loop seizing relation relative to said needle, means for releasably securing said shuttle housing in angularly adjusted position relative to the axis of said shuttle shaft to provide for adjustment of said shuttle relative to said bed plate, and means for bed having a bed plate,'a needle mounted in said frame for endwise reciprocation and adapted to penetrate said bed plate to define a point of stitch formation thereon, and a shuttle mechanism comprising a shuttle housing, a shuttle driving shaft journaled in said shuttle housing, an internal circular raceway formed in said shuttle housing coaxially of the, axis of said shuttle driving shaft, a shuttle having a peripheral bearing rib journaled in said raceway, a shuttle driver carried by said shuttle driving shaft and operatively engaging, said shuttle for imparting oscillation to said shuttle upon oscillation of said shuttle driving shaft, a bus-hing mounted in said bed and having a free end, a shuttle shaft journaled longitudinally of said bed in said bushing on an axis parallel to said bed plate, means forimparting oscillation to said shuttle shaft, said shuttle housing being mounted on the free end of said bushing with said shuttle driving shaft on an axis normal to the axis of said shuttle shaft and substantially parallel to said bed plate and for angular adjustment of said shuttle housing about the axis of said shuttle shaft and with said shuttle disposed in loop seizing relation relative to said needle, means for releasably securing said shuttle housing in angularly adjusted position relative to the axis of said shuttle shaft to provide for adjustment of said shuttle relative to said bed plate, and means for connecting said shuttle shaft and said shuttle driving shaft for oscillation of said shuttle driving shaft upon oscillation of said shuttle shaft.

References Cited in the file of this patent Great Britain May 11, 1960 

